A leakage detection protection circuit comprises null and live wires in power input and power output ends. Also included are induction coil (L1), self-excitation coil (L2), control chip (IC1), silicon controlled rectifier (V4), rectifier diode (V1), resistor (R1), filter capacitor (C3), trip coil (SOL) with built-in iron core, and main circuit switches (KR2-1, KR2-2) linked with a reset button. At least one single-pole double-throw analog power supply switch (KR-2) is linked with the reset button and comprises a dynamic contact rod (C) and first and second static contact terminals (A) and (B). The analog power supply switch is configured so that the circuit has test analog leakage current, working power supply, or no current based on the position of the dynamic contact rod (C) with respect to the static contact terminals and also based on the position of the reset button.